atspi: Add pango utilities

This code is more or less a direct copy of what
we had in gtkpango.c in 3.x.

gtk/a11y/gtkatspipangoprivate.h

@@ -0,0 +1,54 @@
+/* gtkatspipangoprivate.h: Utilities for pango and AT-SPI
+ * Copyright 2020 Red Hat, Inc
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#pragma once
+
+#include <pango/pangocairo.h>
+#include "gtkatspiprivate.h"
+
+G_BEGIN_DECLS
+
+void gtk_pango_get_default_attributes (PangoLayout     *layout,
+                                       GVariantBuilder *builder);
+void gtk_pango_get_run_attributes     (PangoLayout     *layout,
+                                       GVariantBuilder *builder,
+                                       int              offset,
+                                       int             *start_offset,
+                                       int             *end_offset);
+
+char *gtk_pango_get_text_before (PangoLayout           *layout,
+                                 int                    offset,
+                                 AtspiTextBoundaryType  boundary_type,
+                                 int                   *start_offset,
+                                 int                   *end_offset);
+char *gtk_pango_get_text_at     (PangoLayout           *layout,
+                                 int                    offset,
+                                 AtspiTextBoundaryType  boundary_type,
+                                 int                   *start_offset,
+                                 int                   *end_offset);
+char *gtk_pango_get_text_after  (PangoLayout           *layout,
+                                 int                    offset,
+                                 AtspiTextBoundaryType  boundary_type,
+                                 int                   *start_offset,
+                                 int                   *end_offset);
+char *gtk_pango_get_string_at   (PangoLayout           *layout,
+                                 int                    offset,
+                                 AtspiTextGranularity   granularity,
+                                 int                   *start_offset,
+                                 int                   *end_offset);
+
+G_END_DECLS

gtk/a11y/gtkatspiprivate.h

@@ -228,4 +228,22 @@ typedef enum {
     ATSPI_RELATION_LAST_DEFINED,
 } AtspiRelationType;
 
+typedef enum {
+    ATSPI_TEXT_BOUNDARY_CHAR,
+    ATSPI_TEXT_BOUNDARY_WORD_START,
+    ATSPI_TEXT_BOUNDARY_WORD_END,
+    ATSPI_TEXT_BOUNDARY_SENTENCE_START,
+    ATSPI_TEXT_BOUNDARY_SENTENCE_END,
+    ATSPI_TEXT_BOUNDARY_LINE_START,
+    ATSPI_TEXT_BOUNDARY_LINE_END,
+} AtspiTextBoundaryType;
+
+typedef enum {
+  ATSPI_TEXT_GRANULARITY_CHAR,
+  ATSPI_TEXT_GRANULARITY_WORD,
+  ATSPI_TEXT_GRANULARITY_SENTENCE,
+  ATSPI_TEXT_GRANULARITY_LINE,
+  ATSPI_TEXT_GRANULARITY_PARAGRAPH
+} AtspiTextGranularity;
+
 G_END_DECLS

gtk/a11y/meson.build

@@ -13,5 +13,6 @@ if gtk_a11y_backends.contains('atspi')
     'gtkatspicontext.c',
     'gtkatspiroot.c',
     'gtkatspiutils.c',
+    'gtkatspipango.c',
   ])
 endif